Envelop.



GEORGE E. THOBNBURG, 0F WINCHESTER, INDIANA.

l ENVELOP.

Specification of Letters Patent.

Patented Aug. 26,1913@ Application fried May 1 2, 1913. Serial )10.767,185.

To all whom t may concern:

Be it known that I, GEORGE. E. THORN-l BURG, a citizen ofthe United States, residing at Winchester, in the county of Randolph and State of Indiana, have invented a new and useful Envelop, of which the following is a specification.

The object of my invention is to provide an envelop of novel construction in which all flaps interlock to securely fasten the envelop without the use of adhesive, and which also affords means for inspecting the oontents without unfastening all flaps of the envelop.

It is also an .object of my invention to provide an envelop of novel construction that when sealed withv adhesive can not be opened or broken into without tearing.

It is also an obj eet of my invention to provide an envelop or paclret-closure of the novel construction set forth suitable for wrapping all classes `of mail, etc.

My invention is set forth in the accompanying drawings in which- Figure 1 is a plan view of the back of the envelop, folded except for the top flap; Fig. 2 is a plan view showing the end flaps folded and interloeked but with the top and bottom flaps open; Fig. 3 is an enlarged cross sectional view through the' center of the envelop; Fig. 4 is a plan view of the envelopblank, before foldlng.

As illustrated in Fig. 4, which shows the envelop-blank, I provide a body or front portion l; a top Hap 2, having a tongue 3; a lbottom flap 4 having a segmental slot 5; and end flaps G and 8. End iaps 6 and 8 have concave longitudinal edges so that when folded together over the inclosure, the nature of the contents may be noted without unfastening the end flaps. End flap G is provided with a substantially vertical slit 7, as a locking means. End Hap 8 is provided with a tongue 9 vertically extending lip 10. An angular slot is formed in end iap 8 oy edges 11 and 12, the latter corresponding substantially with slot 5 and tongue 3.

In operation end flap Sis folded over end .flap 6; tongue 9 is inserted through slit 7; and the two flaps are retained in looked relation by lip 10, as shown in Fig. 2. Bottom flap 4 is then folded over end flaps 6 andati,

as shown in Fig. 1, inv which position the base line of segmental slot 5 substantially coincides with edge 12 of flap 8. Top flap 2 is then folded over bottom flap l and tongue 3 is inserted through segmental slot 5 and also inserted through the angular slot formed by edges 11 and 12 of flap 8. Bottom flap i is thus held in a locked relation by means of tongue 3, with end flap 8, which in turn is-locled to flap 6. The relative position of the tongue and flaps and manner in which it is inserted to securely lock the envelop is illustrated in Fig. 3. A securely fastened envelop is thus provided adapted for inelosing various classes of unsealed mail matter, ete.

It is also within the contemplation of in invention to add the usual adhesive or sea ing gum along the inner edges of bottom flap 4: and top apv2 and tongue 3, to provide a safety envelop for first class mail, to provide an envelop for first class mail which can not be opened without tearing, as tongue 3 would be inserted through segmental slot 5 and beneath edge 12 of flap 8 and sealed to end Hap 6, which is the innermost flap. The segmental shape of slot 5 would permit of the insertion of the gulnmed tongue easily without scraping olf the adhesive.

Vhat I claim is:

An envelop comprising a front portion; end {iaps foldable toward each other, one of the flaps being provided with a substantially vertical slit extending from the edge of the flap approximately to its Vcenter and the opposite flap being provided with an end tongue insertible through the aforesaid slit in the opposite flap, and having a vertically extending lip formed on the tongue to secure the two end flaps in locked relation, and also having an angular slot opposite the aforesaid lip; and a bottom flap foldable over the end flaps and having a slot substantially coinciding with the angular slot; and a top flap fold-able over the bottom flap and `having a tongue insertible through the slotted bottoni flap and slotted end flap, whereby 

